(620d) Acitve Toroids Conference: AIChE Annual MeetingYear: 2016Proceeding: 2016 AIChE Annual MeetingGroup: Engineering Sciences and FundamentalsSession: Active Colloidal Systems Time: Thursday, November 17, 2016 - 9:15am-9:30am Authors: Chang, Y. W., Georgia Institute of Technology Fernandez-Nieves, A., Georgia Institute of Technology Garcia, A., Georgia Institute of Technology Cruz, R. Fragkopoulos, A. The study of multicellular sheets is of great interest because of their important role in tissue development, morphogenesis, and wound healing. In confluent layer of epithelia at sufficiently high densities, cells coordinate their behavior and can collectively respond to physical and chemical stimuli. For example, heterogeneity of tissue tension within a planar 2D monolayer has been shown to correlate with the collective cell migration pattern as well as with the local increase in cell proliferation. However, much less is known about how cells respond to out-of-plane curvatures that are on the order of 1 to 100 cell lengths. Here, we investigate the proliferation and structure of MDCK on toroidal hydrogel substrates; unlike spherical or planar substrates, toroidal substrates have regions of both positive and negative Gaussian curvature. We can control the range of curvature via tuning the size and aspect ratio of the hydrogel torus, allowing us to explore the relation between substrate curvature, cell arrangement, and cell proliferation.